Study on welding sequence of butt-welded structures based on equivalent heat source parameter

A thermo-elastic-plastic numerical method based on the hybrid inversion combing experiment results and numerical results was developed. The influence of various factors in the welding process on the welding deformation and residual stress was taken into account through the equivalent heat source parameter (EHSP). The out-of-plane displacement and residual stress of the butt-welded plate were measured firstly with electrical measurement method and hole-drilling method respectively. Then, a function was established to evaluate the standard error (SE) employing different heat source parameters between numerical and experimental results, and the EHSP corresponding to SEmin for the current material and welding conditions was inversed. At last, the EHSP was applied to the investigation of welding sequence. This method is also suitable for other welding methods and weld types.